Resumo:

The cerrado vegetation areas within Mato Grosso State have been largely
devastaded and few efforts have been done to intercept this situation. Conservation and
vegetational diversity restoration studies are essential and strenghten with the
Floresteca Agroflorestal Ltda company purposes, which embodies the environmental
adjustment of its production properties. For this matter, ecological restoration through
natural regeneration assistance should be the most appropriate technique. This is due to
the fact that there are plenty natural remnants in this region, which assure a reasonable
level of resilience, based on a high regeneration potencial, mainly through root
sprouting. The attempts of this study is to evaluate the natural regeneration potencial as
a technique to restore cerrado vegetation areas, previously used as pasture, analysing
different management methods with ecological processes and vegetational diversity
restoration purposes. To evaluate natural regeneration, fifty 10x10meters plots (total of
5000m2) were randomly distributed. A previous evaluation of regeneration within these
plots was made before treatments were applied. Five treatments were applied, each one
represented by 10 replicates; treatments were: control (T); manual weed in a cicle
around regenerating individuals (C); manual weed in a cicle around regenerating
individuals and manuring (A); complete manual removal of weeds (L); and complete
chemical removal of weeds (Q). All regenerating individuals higher than 20cm were
identified and height measured. A total of eight measurements were taken within 16
months, in a 2 monthly basis interval. A total of 2696 individuals (5392 ind.ha-1) were
sampled, with 128 (4,75%) dead individuals and 2568 living ones, represented by 90
morphospecies distributed within 69 genera and 32 botanical families (one remained
unknown). Shannon ́s diversity index was calculated on H’=3.78 nats.individual-1, while
Pielou ́s equability index was of J’=0.87. Regarding density enhancement analysis, (L)
treatment presented better results when compared to control (T), probably because
weed removal allowed better visualization of regenerating individuals. However, when it
comes to height increase, this same treatment (L) presented the lowest values.
Chemical weed control treatment (Q) did not affect natural regeneration, and height
grothw was higher than those for control treatment (T), although the enhanced number
of individuals was the lowest one. The second best treatment for height increase was
(A), although in a similar way to treatment (C), density enhancement showed no
significant difference when compared to (T). Only at the last taken measurement (C)
treatment presented higher height increase than control.